Postgres and Open Source Experts

In PostgreSQL, the OFFSET clause is used to skip some records before returning the result set of a query. By default, the OFFSET clause skipped the records from the top.

In PostgreSQL, the EXCEPT operator is used to compare multiple tables. It executes two SELECT queries and retrieves only those records that are not available in the second SELECT query.

In Postgres, the NOW() function retrieves the current date and time along with the time zone(based on the database server’s setting).

PostgreSQL provides a pg_relation_size() function to get the size of a particular table. The “pg_size_pretty()” function is used to get the table’s size in a human-readable format like KBs, MBs.

CURRENT_DATE is one of the Postgres built-in date functions that retrieve the current/today’s date. It doesn’t take any argument.

PostgreSQL offers a GRANT statement that is used to assign privileges to the database objects. In Postgres, you can grant all privileges to a user via the "GRANT ALL" statement.

UNIQUE constraints can be dropped by running the ALTER TABLE command with the "DROP CONSTRAINT" clause followed by the constraint’s name.

PostgreSQL provides a built-in DIV() function that takes two numeric values as arguments, performs division on them, and retrieves the resultant integer.

In Postgres, double hyphen “--” sign is used for single-line comments, while to use multi-line comments, you need to enclose the comments within “/*” and “*/”.

To create an array in Postgres, users must specify the column name, then the data type, followed by the square brackets “[]”.